Java Enhanced For Loop

Java enhanced for loop

Created By: chatGPT

Java provides an enhanced for loop, also known as the foreach loop, which simplifies the process of iterating over collections and arrays. This loop is particularly useful when you need to access each element without worrying about the index. Below is a basic explanation of its syntax and usage.

for (Type element : collection) {
    // Use element
}

In this expression, 'Type' represents the type of the elements in the collection, 'element' is a temporary variable that holds the value of the current item being processed, and 'collection' is the array or collection you want to iterate over.

String[] fruits = {"Apple", "Banana", "Cherry"};

for (String fruit : fruits) {
    System.out.println(fruit);
}

This code snippet will print each fruit in the 'fruits' array. The enhanced for loop makes it easier to read and write compared to traditional for loops, especially when you don't need to manipulate the index.

List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);

for (Integer number : numbers) {
    System.out.println(number);
}

You can also use the enhanced for loop with more complex data types, such as objects. The loop can handle collections like ArrayLists, Sets, and arrays of any type.

class Person {
    String name;
    int age;
    
    Person(String name, int age) {
        this.name = name;
        this.age = age;
    }
}

List<Person> people = new ArrayList<>();
people.add(new Person("Alice", 30));
people.add(new Person("Bob", 25));

for (Person person : people) {
    System.out.println(person.name + " is " + person.age + " years old.");
}

In this example, we define a Person class and create a list of Person objects. The enhanced for loop is then used to print each person's name and age. Using the enhanced for loop helps maintain clean and concise code.

Set<String> uniqueWords = new HashSet<>(Arrays.asList("Java", "Python", "C++"));

for (String word : uniqueWords) {
    System.out.println("Programming Language: " + word);
}

Here, an enhanced for loop iterates over a Set of unique words. It highlights how the enhanced for loop works with different types of collections available in Java.

int[] numbersArray = {1, 2, 3, 4, 5};

for (int number : numbersArray) {
    System.out.print(number + " ");
}

Finally, an enhanced for loop can be used with an array of primitive types. This not only improves readability but also helps to avoid common errors associated with index-based looping.

// Example of enhancing with nested loops
List<List<Integer>> matrix = new ArrayList<>();

for (int i = 0; i < 3; i++) {
    List<Integer> row = new ArrayList<>();
    for (int j = 0; j < 3; j++) {
        row.add(i * j);
    }
    matrix.add(row);
}

for (List<Integer> row : matrix) {
    for (Integer value : row) {
        System.out.print(value + " ");
    }
    System.out.println();
}